Haworth Tompkins designed The Shed as a monolithic red box, entirely clad with rough-sawn timber boards. This material references the board-formed concrete of Denys Lasdun's celebrated 1970s National Theatre and was intended by the architects to appear as its opposite.

Four towering chimneys rise up from the corners, helping to draw air through the structure using a stack-effect system of natural ventilation. These chimneys were also planned as a reference to the architecture of the theatre and they mimic the angular geometry of its riverside facade.

A temporary foyer is created beneath the existing balconies and leads straight through into the 225-seat auditorium.

Reclaimed chairs provide all of the seating inside the building, while recycled materials were used for all of the cladding and surfaces.

"This collaboration has been a wonderful opportunity to explore the ways in which temporary public buildings can alter our perceptions of places and organisations," said practice director Steve Tompkins. "We hope The Shed will be seen as a playful but thoughtful building, both challenging and complementary to the permanent cultural architecture."

Haworth Tompkins announces the completion of The Shed, a temporary venue for the National Theatre on London's South Bank. The Shed will give the NT a third auditorium while the Cottesloe is closed for a year during the NT Future redevelopment, also designed by Haworth Tompkins.

The artistic programme for The Shed, recently announced by the Director of the National Theatre, Nicholas Hytner, pushes creative boundaries, giving the NT the opportunity to explore new ways of making theatre. In the same way, The Shed has been a test bed for experiment by the architectural design team. Conceived by Haworth Tompkins and regular collaborators Charcoalblue, it was then designed and built in little more than a year, a collaborative process between the building designers, the National Theatre, and theatre-makers who will work in the space, in a way that more closely resembled a theatre show than a conventional construction project.

Above: photograph is by Philip Vile

Its temporary nature, building on Haworth Tompkins' earlier temporary projects like the Almeida Theatre at Gainsborough Studios and King's Cross, permits a structure that can be seen less as a building than as an event or arts installation - a vibrant intervention on London's South Bank that will entrance, and sometimes bewilder, passers-by for a period of twelve months.

Above: photograph is by Philip Vile

The Shed occupies Theatre Square, at the front of the National Theatre, beside the river. Its simple form houses a 225-seat auditorium made of raw steel and plywood, while the rough-sawn timber cladding refers to the National Theatre's iconic board-marked concrete, and the modelling of the auditorium and its corner towers complement the bold geometries of the NT itself. A temporary foyer has been carved out from the space beneath the NT's external terraces and provides easy connection to the existing foyers. The Shed's brilliant red colour covering the entire mass of a form without doors or windows, announces its arrival boldly against the concrete bulk of the NT, giving it a startling and enigmatic presence.

Above: photograph is by Philip Vile

The Shed also represents another step in Haworth Tompkins' ongoing project to research sustainable ways of making theatres. Built of materials that can be 100% recycled and fitted out with re-used seating, The Shed is naturally ventilated, with the four towers that draw air through the building providing its distinctive form.